From: Akihiko Odaki Date: Thu, 23 Apr 2026 13:55:22 +0000 (+0900) Subject: audio: Clamp unsigned sample conversion X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=698399705c016b6f3bf64e466a43882d5873bb50;p=thirdparty%2Fqemu.git audio: Clamp unsigned sample conversion clip_*_uint32_t() returns 0 when v == 1.f because it computes the result as (IN_T)((v * ((mixeng_real)IN_MAX / 2.f)) + HALF): - (v * ((mixeng_real)IN_MAX / 2.f)) + HALF == 0x100000000.f, which does not fit in uint32_t. - (v * ((mixeng_real)IN_MAX / 2.f)) == 0x80000000.f - ((mixeng_real)IN_MAX / 2.f) == 0x80000000.f - (mixeng_real)IN_MAX == 0x100000000.f because 0xffffffff cannot be represented exactly in float. - HALF == 0x7fffffff, which is implicitly converted to 0x80000000.f. Clamp the result to avoid the overflow. Signed-off-by: Akihiko Odaki Acked-by: Marc-André Lureau Message-Id: <20260423-audio-v1-2-e1d6b65c76f9@rsg.ci.i.u-tokyo.ac.jp> --- diff --git a/audio/mixeng_template.h b/audio/mixeng_template.h index 881653c44bf..5b0014bdd9a 100644 --- a/audio/mixeng_template.h +++ b/audio/mixeng_template.h @@ -65,7 +65,9 @@ static inline IN_T glue (clip_, ET) (mixeng_real v) #ifdef SIGNED return ENDIAN_CONVERT((IN_T)(v * (((mixeng_real)IN_MAX - IN_MIN) / 2.f))); #else - return ENDIAN_CONVERT((IN_T)((v * ((mixeng_real)IN_MAX / 2.f)) + HALF)); + return ENDIAN_CONVERT(MIN((int64_t)((v * ((mixeng_real)IN_MAX / 2.f)) + + HALF), + IN_MAX)); #endif }